[scl.org] Setting SCL RPM build options in COPR?

[Petr Kubat]

Hi Nick,

sending the mail again since I did not send the reply to list before 
(sorry!).

On 09/19/2017 08:16 AM, Nick Coghlan wrote:
> On Mon, Sep 18, 2017 at 9:29 PM, Honza Horak <hhorak at redhat.com> wrote:
>> On 09/18/2017 07:29 AM, Nick Coghlan wrote:
>>> 2. Assuming I haven't missed anything, how do the *default* values for
>>> "scl" and "vendorscl" actually get set?
>> We can kinda control what packages are part of the minimal buildroot for
>> every copr or cbs tag -- for SCL case there is the <scl>-build package that
>> sets this 'scl' macro. You can add more macros if you like and they will be
>> defined at a time a particular SRPM/RPM is built. By that trick and changing
>> what macros are defined in <scl>-build, you may basically build more
>> variants of a single SRPM and produce different output.
> That's what I thought, but I couldn't find anything in sclorg-distgit
> that actually *sets* them for the rh-python35 case.
>
> https://github.com/sclorg-distgit/rh-python35/blob/sig-sclo7-rh-python35-rh/macros.additional.rh-python35
> has the comment "the @scl@* macros are defined in
> macros.python3.python33 in python33-python-devel"
>
> That's presumably referring to
> https://github.com/sclorg-distgit/python/blob/sig-sclo7-rh-python35-rh/macros.python3,
> which still doesn't *set* "@scl@" or "@vendorscl@", it assumes they're
> set somewhere else.

The "@scl@" and "@vendorscl@" symbols are replaced by proper values 
during the build of the metapackage [1], and the resulting macros get 
installed using the *-build sub-package [2] as Honza mentioned.

[1] 
https://github.com/sclorg-distgit/rh-python35/blob/sig-sclo7-rh-python35-rh/rh-python35.spec#L113 

[2] 
https://github.com/sclorg-distgit/rh-python35/blob/sig-sclo7-rh-python35-rh/rh-python35.spec#L137

>
> So I'm still confused as to:
>
> - what's up with the "@" symbols in "@scl@" and "@vendorscl@"?
> - where can I find an example package that shows how to define them
> via a package in the buildroot so I can set up sclo-python-preview
> COPR builds?
> - where can I find documentation that explains how to do this when you
> *can't* pass arbitrary RPM build options?
>
> Cheers,
> Nick.
>
> P.S. https://www.softwarecollections.org currently appears to be down
> (I noticed when attempting to find docs about this)
>